rxrpc: Provide a way for AFS to ask for the peer address of a call

Provide a function so that kernel users, such as AFS, can ask for the peer
address of a call:

   void rxrpc_kernel_get_peer(struct rxrpc_call *call,
			      struct sockaddr_rxrpc *_srx);

In the future the kernel service won't get sk_buffs to look inside.
Further, this allows us to hide any canonicalisation inside AF_RXRPC for
when IPv6 support is added.

Also propagate this through to afs_find_server() and issue a warning if we
can't handle the address family yet.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 11 insertions, 9 deletions

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index ca32d891bbc3..77ee481059ac 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -167,9 +167,9 @@ static void SRXAFSCB_CallBack(struct work_struct *work)
 static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
 				   bool last)
 {
+	struct sockaddr_rxrpc srx;
 	struct afs_callback *cb;
 	struct afs_server *server;
-	struct in_addr addr;
 	__be32 *bp;
 	u32 tmp;
 	int ret, loop;
@@ -178,6 +178,7 @@ static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
 
 	switch (call->unmarshall) {
 	case 0:
+		rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
 		call->offset = 0;
 		call->unmarshall++;
 
@@ -282,8 +283,7 @@ static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
 
 	/* we'll need the file server record as that tells us which set of
 	 * vnodes to operate upon */
-	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
-	server = afs_find_server(&addr);
+	server = afs_find_server(&srx);
 	if (!server)
 		return -ENOTCONN;
 	call->server = server;
@@ -314,12 +314,14 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call,
 					       struct sk_buff *skb,
 					       bool last)
 {
+	struct sockaddr_rxrpc srx;
 	struct afs_server *server;
-	struct in_addr addr;
 	int ret;
 
 	_enter(",{%u},%d", skb->len, last);
 
+	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
+
 	ret = afs_data_complete(call, skb, last);
 	if (ret < 0)
 		return ret;
@@ -329,8 +331,7 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call,
 
 	/* we'll need the file server record as that tells us which set of
 	 * vnodes to operate upon */
-	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
-	server = afs_find_server(&addr);
+	server = afs_find_server(&srx);
 	if (!server)
 		return -ENOTCONN;
 	call->server = server;
@@ -347,11 +348,13 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call,
 						struct sk_buff *skb,
 						bool last)
 {
+	struct sockaddr_rxrpc srx;
 	struct afs_server *server;
-	struct in_addr addr;
 
 	_enter(",{%u},%d", skb->len, last);
 
+	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
+
 	/* There are some arguments that we ignore */
 	afs_data_consumed(call, skb);
 	if (!last)
@@ -362,8 +365,7 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call,
 
 	/* we'll need the file server record as that tells us which set of
 	 * vnodes to operate upon */
-	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
-	server = afs_find_server(&addr);
+	server = afs_find_server(&srx);
 	if (!server)
 		return -ENOTCONN;
 	call->server = server;